Manufacture of chewing-gum.



J. n. DARLING. MANUFACTURE or CHEWING GUM. I APPLICATION FILED JULY 2, 190B.

947,635, I Patented Jan. 25, 1910.

2 SHEETS-SHEET 1.

z zzc li WITNESSESI- INVENTORZ J.- D. DARLING. MANUFAGTUEE 0F CHEWING GUM. APPLICATION FILED JULY 2, 1908.

947,635, I Patented Jan; 25, 1910.

2 SHEETS-SHEETB.

"TED sTATEs PATENT oiuucn.

JAMES D. DARLING,'OF PHILADELPHIA,- PENNSYLVA NIA, ASSIGNOR TO KEYSTONE TRADING COMPANY, A CORPORATION Oi? NEW JERSEY.

MANUFACTURE or CHEWING-GUM.

Original application filed December 31,

To all whom it may coneernt Be itknown that I, JAMES D. I)ARL11\'G, of Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in the Manufacture of Chewing-Gum, whereof the following is a specification, reference being had to the accompanying drawings.

Hitherto chewing gum has been manufactured from ccrtain resinous gums, notably from spruce gum or from gum chicle. These substances possess by nature ,the required consistency and especially the high degree of ductility and plasticity with absence of resiliency, which. is necessary for a masticatory gum. l l have discovered that a substance having similar qualities to the above and "suitable for the same purposes, may be manufactured from certain low grade rubbers. Ordinarily rubber or caoutchouc in all its forms is unsuited for mastication, because of its toughness and high resiliency. It also usually has a disagreeable taste and odor. Low grade rubbers are characterized by the presence of a high percentage of resin, but by reason-of the rubber which they contain cannot ordinarily be used in the manufacture of chewin gum. I have found that bythe process whlch I will describe, it ispossible to convert such a low grade rubber into a superior masticatory mun. To accomplish this, it is necessary to cleanse and purify the crude product, whenever, as is usually the case, it is accompanied by impurities which give it a disagreeable taste or odor. It is also necessary to render the rubber content less tough and resilient. By the process which I have discovered, I accomplish both these ends, whereby I am able to produce from cheap low grade rubber an entirely satisfactory masticatory gum, having the peculiar cohesiveness, plasticity, and due tility which is required, not adhesive to the teeth, not tough, and not resilient.- and-also odorless and tasteless. j In the present specification the word resiliency, is used to denote that quality, highly characteristic of india rubber, by which it completely restores or reforms itself after distortion by agivcn strain, as Soon as the strain is removed. It is opposed to plasticity, by which is'meant the capacity Specification of Letters Patent.

190;, Serial No. 408,721'.

1908; Serial No. 441,517.

Patented Jan. 25, 15.910.

Divided and this application filed July 2,

an india rubber procured from Borneo, and

sometimes known as 'gutta-jelutong, and under these names largely lmported into this country. Analysis of commercial pontianak shows that exclusive of water, itusually contains about 75% of resin, something over 24% of rubber, and a fraction of 1% of ash. Authorities lunvever state that at times the resin content may reach 90%. This material as imported into this country, is entirely unsuitable for use as a chewing gum, not only because of tlie impurities which it contains, but because the rubber content renders it. too tough and too resilient. But by subjecting this material to the process of treatment which I will describe, I am'able to produce an exceedingly desirable chewing gum at alow price; v

In practicing my process I take the crude pontianak of commerce, and after cleaning 1t, cut or chip it up into small pieces, preferably by a mechanical cutter. This comminuted material is then placed in a suitable receptacle and there boiled for inconsiderable time in an alkaline solution. For this purpose the use of twenty-five pounds of caustic soda to one hundred gallons of water will produce the proper result. The boiling is continued until all the impurities present in the crude article have sunk to the bottom, while the mixture of rubber and resin, purified and/considerably changed in its physical characteristics, floats at orncar the surface as a spongy mass. When freed from the'alkaline liquor this mass is odorlessand tasteless, but still somewhat tough and resilient. This rodu'ct is removed and after repeated washings is subjected to-apull- .iug or kneading operation, by which its physical qualities are further changed; For

this purpose I prefer to. use the apparatus In the drawings, 1, is a hopper mounted on standards 2. A shaft 3, is conveniently journaled in said standards 2, and carries the tight and loose pulleysa, and 5, and also the pinions 6, 6, which are keyed thereto adjacent to each end of the hopper 1.

Pinions 6, 6, transmit motion to the gears 7, 7, which in turn mesh with the gears 8, 8.

Gears 7, 7, and 8, 8, are fast upon trunnions 9, 9, and 10, 10, to which are fastenedthe revolving blades 11, and 12, respectively. Said blades 11, and 12, are spiral in form and their sharp edges 13, are adapted to shearagainst the edge 14, on the bottom of hopper 1, as can be clearly seen in Fig. II.

The blade 12, revolves in an opposite direction to and twice as fast as the blade 11,

7 by virtue of therelation of the gears 7, 7, to

the gears 8, 8, thus thoroughly mixing by a combined shearing and tearing action.

It will be understood that the machine above described forms no part of my invention but is well adapted to perform the pulling, cutting and kneadin which is necessary during my process. During the treatment of the material in this apparatus it is maintained at a temperature of, between 200 and 300 Fahrenheit.

The treatment is continued for a considerable time, determined by observation, and as 'a result the physical characteristics of the rubber are markedly changed. The rubber content of the mass will be found to have lost its toughness and resiliency and the mass will-have become plastic, tenacious and extremely ductile,so that it may be pulled out in fine threads of-almost indefinite length with little or no resiliency, and these qualities are retained by it for a long time. This product is eminently suited for use in the manufacture of chewing gum. I find that under .some circumstances, the substance is improved by the addition thereto of 'about five per cent. of a pure vegetable wax or some other similar waxy substance. This may be introduced in the mixer and aids in giving grade rubber into a chewing gum, to whichend the large resin content of the low grade rubber materially aids. The method of pu- -rifying the eomlnercial low grade rubber which I have described is also of my invention, and, as I believe, novel.

The present application is a division of the application Serial No. 408,721, filed by me under date of December 31st, 1907, and in which I claim the new product which results from my process.

Having thus described my invention, I claim:

1. The process of converting a low grade rubber, containing a high percentage of resin, into a masticatory gum which consists in subjecting it to a continued kneading operation While maintained at a temperature of two or three hundred degrees Fahrenheit, "whereby the resiliency of the rubber content is destroyed and the mass is rendered plastic.

2. The process of converting a low grade rubber, containing a high percentage of resin, into a masticatory gum which consists in boilin it in a comminutcd state in an alkaline so ution and then subjecting it to a continued kneading operation while main tained at a temperature of two or three hundred degrees Fahrenheit,- Whereby the resiliency of the rubber content is destroyed and the mass is rendered plastic.

. The process of manufacturing chewing gum which consists in purifying crude pontianak rubber; and then kneading it while maintained at a temperature of about two orvthree hundred degrees Fahrenheit until the resiliency of therubber is destroyed and the mass is rendered plastic. 0 v

In testimony whereof, I have hereunto signed my name, at Philadelphia, Pennsylvania, this twenty-seventh day of June, 1908.

' JAMES D. DARLING. Wi tn esses JAMES H. BELL, E. L. FULLERTON. 

